0.0
NA
CVE-2026-91096
Proxygen WebTransport Use-After-Free Vulnerability
Description

In proxygen from v2024.10.28.00 until v2026.09.28.00, WebTransportImpl::terminateSessionStreams (WebTransportImpl::destroy in releases before v2025.08.18.00) failed to unregister read callbacks for streams that were no longer open before destroying them. The transport could then invoke a read callback that had been freed.

INFO

Published Date :

Sept. 28, 2026, 9:17 p.m.

Last Modified :

Sept. 28, 2026, 9:17 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-91096 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Facebook proxygen
Solution
Update Proxygen to resolve memory corruption issues related to stream handling.
  • Update Proxygen to a version after v2026.09.28.00.
  • Apply necessary patches if using older versions.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-91096.

URL Resource
https://github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083
https://www.facebook.com/security/advisories/cve-2026-91096
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-91096 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-91096 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-91096 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-91096 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 28, 2026

    Action Type Old Value New Value
    Added Description In proxygen from v2024.10.28.00 until v2026.09.28.00, WebTransportImpl::terminateSessionStreams (WebTransportImpl::destroy in releases before v2025.08.18.00) failed to unregister read callbacks for streams that were no longer open before destroying them. The transport could then invoke a read callback that had been freed.
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/91xxx/CVE-2026-91096.json">CVE-2026-91096</a>
    Added Reference https://github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083
    Added Reference https://www.facebook.com/security/advisories/cve-2026-91096
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.